1. Field of the Invention
The invention relates to a display device including a pixel array in which pixel circuits are arranged in a matrix state and a display drive method thereof, and relates to, for example, a display device using an organic electroluminescence element (organic EL element) as a light emitting element.
2. Description of the Related Art
An image display device in which an organic EL element is used in a pixel is developed, for example as shown in JP-2003-255856 and JP-2003-271095 (Patent Documents 2 and 3). Since the organic EL element is a self-luminous element, it has advantages such that visibility of images is higher than, for example, a liquid crystal display, a backlight is not necessary and response speed is high. The luminance level (tone) of each light emitting element can be controlled by a value of current flowing therein (so-called current-control type).
The organic EL display has a passive matrix type and an active matrix type as a drive method in the same manner as the liquid crystal display. The former has problems such that it is difficult to realize a large-sized as well as high-definition display though it has a simple configuration, therefore, the active-matrix type display device is vigorously developed at present. The display device of this type controls electric current flowing in the light emitting element in each pixel circuit by an active element (commonly, a thin film transistor: TFT) provided inside the pixel circuit.